The working process of a typical fax machine in fax transmission of a document generally includes the steps as follows:
(1) Separate the first page form the remaining documents;
(2) Feed the first page into scanning means;
(3) Scan the first page at a predetermined speed and send out a serious of codes representing the graphical data of the page according to communication protocols;
(4) Repeat the above steps until no documents remains.
Most fax machines use a combination of an electromagnetic clutch and a single-directional bearing to achieve the purpose of separating and feeding the document papers for accurately scanning the graphical data. However, this increases manufacturing cost of the fax machines, since the electromagnetic clutch and the single-directional bearing are expensive and difficult to assemble.